view layer/ColourScale.cpp @ 1447:8afea53332f3 single-point

Add option to make pane sizes auto-resize-only (i.e. remove user control via a splitter); also place alignment views above panes instead of below, meaning the extra bit of space that we currently have for the pane without one at least goes to the primary pane

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006-2016 Chris Cannam and QMUL.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#include "ColourScale.h"

#include "base/AudioLevel.h"
#include "base/LogRange.h"

#include <cmath>
#include <iostream>

using namespace std;

int ColourScale::m_maxPixel = 255;

ColourScale::ColourScale(Parameters parameters) :
    m_params(parameters),
    m_mapper(m_params.colourMap, m_params.inverted, 1.f, double(m_maxPixel))
{
    if (m_params.minValue >= m_params.maxValue) {
        SVCERR << "ERROR: ColourScale::ColourScale: minValue = "
             << m_params.minValue << ", maxValue = " << m_params.maxValue << endl;
        throw std::logic_error("maxValue must be greater than minValue");
    }

    m_mappedMin = m_params.minValue;
    m_mappedMax = m_params.maxValue;

    if (m_mappedMin < m_params.threshold) {
        m_mappedMin = m_params.threshold;
    }
    
    if (m_params.scaleType == ColourScaleType::Log) {

        // When used in e.g. spectrogram, we have a range with a min
        // value of zero. The LogRange converts that to a threshold
        // value of -10, so for a range of e.g. (0,1) we end up with
        // (-10,0) as the mapped range.
        // 
        // But in other contexts we could end up with a mapped range
        // much larger than that if we have a small non-zero minimum
        // value (less than 1e-10), or a particularly large
        // maximum. That's unlikely to give us good results, so let's
        // insist that the mapped log range has no more than 10
        // difference between min and max, to match the behaviour when
        // min == 0 at the input.
        //
        double threshold = -10.0;
        LogRange::mapRange(m_mappedMin, m_mappedMax, threshold);
        if (m_mappedMin < m_mappedMax + threshold) {
            m_mappedMin = m_mappedMax + threshold;
        }
        
    } else if (m_params.scaleType == ColourScaleType::PlusMinusOne) {
        
        m_mappedMin = -1.0;
        m_mappedMax =  1.0;

    } else if (m_params.scaleType == ColourScaleType::Absolute) {

        m_mappedMin = fabs(m_mappedMin);
        m_mappedMax = fabs(m_mappedMax);
        if (m_mappedMin >= m_mappedMax) {
            std::swap(m_mappedMin, m_mappedMax);
        }
    }

    if (m_mappedMin >= m_mappedMax) {
        SVCERR << "ERROR: ColourScale::ColourScale: minValue = " << m_params.minValue
             << ", maxValue = " << m_params.maxValue
             << ", threshold = " << m_params.threshold
             << ", scale = " << int(m_params.scaleType)
             << " resulting in mapped minValue = " << m_mappedMin
             << ", mapped maxValue = " << m_mappedMax << endl;
        throw std::logic_error("maxValue must be greater than minValue [after mapping]");
    }
}

ColourScale::~ColourScale()
{
}

ColourScaleType
ColourScale::getScale() const
{
    return m_params.scaleType;
}

int
ColourScale::getPixel(double value) const
{
    double maxPixF = m_maxPixel;

    if (m_params.scaleType == ColourScaleType::Phase) {
        double half = (maxPixF - 1.f) / 2.f;
        int pixel = 1 + int((value * half) / M_PI + half);
//        SVCERR << "phase = " << value << " pixel = " << pixel << endl;
        return pixel;
    }
    
    value *= m_params.gain;
    
    if (value < m_params.threshold) return 0;

    double mapped = value;

    if (m_params.scaleType == ColourScaleType::Log) {
        mapped = LogRange::map(value);
    } else if (m_params.scaleType == ColourScaleType::PlusMinusOne) {
        if (mapped < -1.f) mapped = -1.f;
        if (mapped > 1.f) mapped = 1.f;
    } else if (m_params.scaleType == ColourScaleType::Absolute) {
        if (mapped < 0.f) mapped = -mapped;
    }

    mapped *= m_params.multiple;
    
    if (mapped < m_mappedMin) {
        mapped = m_mappedMin;
    }
    if (mapped > m_mappedMax) {
        mapped = m_mappedMax;
    }

    double proportion = (mapped - m_mappedMin) / (m_mappedMax - m_mappedMin);

    int pixel = 0;

    if (m_params.scaleType == ColourScaleType::Meter) {
        pixel = AudioLevel::multiplier_to_preview(proportion, m_maxPixel-1) + 1;
    } else {
        pixel = int(proportion * maxPixF) + 1;
    }

    if (pixel < 0) {
        pixel = 0;
    }
    if (pixel > m_maxPixel) {
        pixel = m_maxPixel;
    }
    return pixel;
}

QColor
ColourScale::getColourForPixel(int pixel, int rotation) const
{
    if (pixel < 0) {
        pixel = 0;
    }
    if (pixel > m_maxPixel) {
        pixel = m_maxPixel;
    }
    if (pixel == 0) {
        if (m_mapper.hasLightBackground()) {
            return Qt::white;
        } else {
            return Qt::black;
        }
    } else {
        int target = int(pixel) + rotation;
        while (target < 1) target += m_maxPixel;
        while (target > m_maxPixel) target -= m_maxPixel;
        return m_mapper.map(double(target));
    }
}